C&C: My first attempt...

I am looking for some help to understand what I could be doing better. This is my first Foray into Digital Photography I took several shots at varying Apertures in Aperture Priority and picked the best for some post processing. It seems as if the original photo did not grab the vibrance of the colour of the castle. That was my main focus on PP.

I welcome any feedback on anything (Composition, Post Processing, etc). I am just trying to learn. Thanks